Particle System is on the wrong side?

I am VERY new to blender and 3D modeling itself and have wound up stuck on a step within a donut creation tutorial. This step involves creating sprinkles via a particle system. I have successfully created the particle system and added a weighted paint group to determine where the sprinkles should generate, however, I am seeing quite literally the opposite of what I “should” see per the video. The sprinkles in weighted render mode are showing the opposite side of the red weight paint area, instead of inside it, and to make matters worse, the sprinkles are rendering on the bottom of the icing instead of the top. I have verified the normals appear to be facing the correct way (as seems to be a common issue in my searches. Any help is appreciated to understand what’s happening. Thank you!!

In “Vertex Groups” where you have chosen your weight map under “density” click once on the double arrow <-> to invert the map.

Wow, that was easier than I expected. Now the only remaining issue is that the particles seem to be building UNDER my mesh instead of on top of it in the render. Any ideas here? You can mostly see what I mean through this render. Notice the sprinkles sticking out from under the icing.

Thanks for the first answer though, took almost 2 hours of setting tinkering before I posted on here, can’t believe it was that easy to fix. :sweat_smile:

That problem could have different origins. My first guess is to check the origin of the sprinkle, set it on the middle most down face, or in the middle of the sprinkle at least.

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Okay, this looks likely to be related. One thing that might help get to the bottom of this, no idea if it’s relevant or not, but if on the particle system I check off Children -> “Interpolated” instead of “None” it seems to work.

That said, things look kind of better when I change the origin point but it’s still a little weird.


Origin Change, no interpolation:

Yes, interpolated gives better results. You could increase parents and lower children for better results. But it looks for me like you have an force field active, it looks like they align on an magnetic field or so. You can try and recalculate the normals beside that.

Whelp, I’m a noob! Normals were still screwed up even though that was the first thing I checked (apparently I still have no clue what I’m really looking for :wink: ). I Ctrl+Shift+N’d the icing and bam, like magic it looked good… well, I tinkered with the particle settings after and it looked much, MUCH better than it did. Thank you @rigoletto, I think I’m moving on to figuring out how to texture this bad boy now. :slight_smile: